The United States and Japan will step up their defence cooperation to deal with the threat from nuclear-armed North Korea as tensions in East Asia remain high, officials from the two allies said on Thursday.

NSW man, 71, jailed for brawl killing

Almost a decade after retiring from his criminal career, Donald William Reeves "went overboard" in a drunken fight and killed a former safecracker in his Sydney lounge room.

The 71-year-old pensioner is now back behind bars for at least six years and four months for killing Lynn Tasman Jones, 69, a visitor who had been drinking with Reeves and his housemate at their Millers Point home on June 11, 2009.

Describing the fight which moved from the dining room to the lounge room as something like a scene from "an old western", Justice Stephen Campbell noted both men were in their 60s and "neither was a shrinking violet".

Reeves, who was originally charged with murder, pleaded guilty to the manslaughter of Mr Jones on the basis of his using excessive self-defence.

The father of six children also admitted unlawfully disposing of the body in the Royal National Park.

Mr Jones was reported missing in July 2009, four years before his skeletal remains were found by bushwalkers.

In setting a maximum term of eight years six months in the NSW Supreme Court on Thursday, Justice Campbell referred to Reeves' evidence.